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Background   
Common Midas Concepts   
Getting Started - Part 1   
Getting Started - Part 2   
Working with Files   
Option Trees   
   + Overview   
   - Using an Option Tree   
      - The Path   
         - Using PATH   
         - Using OPTION   
      - Linking to Option Trees   
      - Navigating Using NMD   
      - Using HOMEPATH   
   + Lab 1   
   + Creating an Option Tree   
   + Command Dictionary   
   + Building an Option Tree   
   + Lab 2   
Macros - Part 1 (Basics)   
Macros - Part 2 (Graphics)   
NetBeans - Part 1 (Setup)   
NetBeans - Part 2 (GUIs)   
NetBeans - Part 3 (Profiler)   
Eclipse - Part 1 (Setup)   
Eclipse - Part 2 (GUIs)   
Primitives   
Applets & WebStart   
Maps & Imagery   
X-Midas Interoperability   
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Installing NeXtMidas   
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File Handlers   


  • The Option Tree Path:
    • The path is the list of option trees that are in use.
      • The SYS option tree must always be included.
    • The path is ordered such that option trees with higher standing appear first.
      • If a command typed in matches commands in multiple option trees the one in the option tree listed first will be used.
        • This feature can be overridden by explicitly indicating the option tree to be used. This is done by appending ";<opt>" at the end of the command name (e.g. FFT;SYS).
      • The SYS option tree is always last.
    • The OPT table maps the name of each option tree to its location on disk (or on the web).
      • Option trees that come bundled with NeXtMidas and those linked to under $NMROOT/nxm/ do not need to be included in the OPT table. (More on this later.)
Don't Make This Mistake:
  • Note: Option trees can not be named PATH, CLASSPATH, orNXM since these are special reserved entries in the OPT table. Option tree names must be unique. Additionally the use of the names OPT (the generic name used in many examples) and XM (used when linking to X-Midas) should be avoided.